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Recently, smart sensing/actuation paper has attracted significant interest due to its potential usage as a sustainable component in future electronics, robotics, and intelligent sensing devices. In acknowledging the importance of this topic for the engagement of students at the university level in conjunction with Industrial Revolution 4.0, it is thus quite relevant to establish an approach that can be used to educate the students about the concept of smart paper and its characteristics. To achieve this objective, we have developed a smart paper that is electrically conductive and able to act as a humidity sensor or chemical-driven actuator that can be synthesized in a facile manner through the application of candle soot and commercial crayon on each side of A4 cellulose paper (100 gsm). The sensitivity of the fabricated paper-based sensor toward room humidity is reflected in the changing rate of electrical resistance, which is visually demonstrable by the blooming of an artificial flower made from the paper after exposure to moisture vapor. In conclusion, the activities performed during the reported guidelines may assist in cultivating practical knowledge for colloidal dispersion of carbon-based nanomaterials and chemical-driven actuators among students.

Since 2012, when triboelectric nanogenerators (TENGs) were first reported by Wang and co-workers, various applications have taken advantage of their ability to transform mechanical energy into electrical energy. TENG applications cover many fields, including electronics, physics, materials science, and engineering. The differences in the language used in various research fields makes understanding TENG concepts rather challenging for those outside of the domain. This article provides a practical introduction to triboelectric nanogenerators by applying an inquiry-based learning (IBL) strategy to the assembly and characterization of easily customizable paper-based TENGs. This will allow junior researchers from different fields of materials chemistry to become familiar with the terminology and basic concepts of TENGs, experimentally validate the triboelectric properties of different materials, and construct their first electromechanical sensors and micropower generators.

In the future, learning will be essentially characterized by the ability to regulate the learning process and monitor success independently from a teacher. The technical possibilities offer better access to learning contents, precise and more individualized feedback, and learning phases adapted precisely to the needs of the learner in terms of scope and pace. In this study, we investigate an important aspect of the digitization of teaching/learning processes using the example of laboratory scripts for chemistry students at university. The focus is on looking up terms and concepts in preparation for the lab internships, firstly in a paper-based glossary and secondly in a digital glossary. During a two-day study, a total of 16 students prepared for experiments on two topics with completely identical materials. We then studied the influence of content knowledge, motivation, and cognitive load. While all students show significant learning achievements, there are no significant differences between the groups. Furthermore, results show that pure digitization of information has no effect, despite the theoretically assumed advantages.

During the pandemic caused by SARS-CoV-2 (COVID-19), a paper analytical device (PAD) was proposed as a tool for remote laboratory classes for undergraduate chemistry to teach calibration curve concepts. For this experiment, students were taught how to prepare a PAD, calibrate standard solutions, construct a calibration curve, and treat data obtained by colorimetry digital image, by applying household utensils only. The proposed experiment was evaluated considering remote and in-person courses. More than 80% of the students in both groups reached grades greater than 60%. The students' survey demonstrated that 80 to 100% of the students (n = 6) agreed or strongly agreed that the experiment achieved the learning outcomes concerning the calibration curve. For 50% of the group, it was also found that colorimetric reactions could be more effective than the simple dye impregnation method.

Hands-on experiences in analytical chemistry laboratories are essential to improve students' technical skills on handling analytical glassware and instruments, but the coronavirus pandemic in 2020-2021 disrupted such learning activities. Thus, alternative remote activities are required to supplement practical skills. In this work, a new portable experiment to determine the concentration of Fe(III) by digital image colorimetry with curcumin paper is described. This experiment utilized complexation between Fe(III) and curcumin on a paper substrate, which changed from yellow to red-orange. Then, the RGB intensity changes, obtained using smartphones/devices, were plotted against the Fe(III) standard concentration to construct an external standard calibration curve for determining Fe(III) in unknown solutions. Using students' own smartphone/device enhanced their interest, and the portable small-scale experiment kit enabled a remote hands-on experience at their residence (Lab@Home). The experiment had been implemented both in Lab@Home and in-person formats for three semesters with 591 second-year students majoring in chemistry and other sciences, showing a satisfactory self-evaluated outcome (4.27 from 5) and post-test score (81.5%). The proposed experiment is a showcase to introduce modern analytical chemistry through smartphone/device and digital image colorimetry, while enhancing students' skills and interests in analytical chemistry laboratory.

Although chemistry-focused socio-scientific issues support the 'relevance' model of chemistry education, the related literature has lacked any systematic review handling them together. For this reason, this research aimed to thematically synthesize the research papers on chemistry-focused socio scientific issues (SSI) from 2008 to 2020 and inferentially evaluate them in terms of the relevance model of chemistry education. After searching international and national well-known databases through relevant keyword patterns (e.g., Pattern 1: socio-scientific issues and chemistry education), 65 research papers were apparent for the systematic review. Then, the authors generated primary and secondary codes for the research papers and then inferentially marked their 'relevance' components. The systematic review indicated variation of research areas (e.g., relevance model of chemistry education) and dominant research foci for different themes (e.g., competencies and related variables for the theme 'aims'; pollution, energy, industry and fabrication-based problems for the theme 'SSI'; organic compounds for the theme 'chemistry concepts'). Further, it revealed that the research papers on chemistry-focused SSI had some shortcomings at handling all components of the relevance model in a balanced way. The current research suggests professionally training teachers about how to integrate chemistry-focused SSI and the relevance model into school chemistry.

We describe an iodometric titration method for the determination of ascorbic acid using a microfluidic paper-based analytical device([mu]PAD). The ascorbic acid was detected by measuring the length of the blue band formed in a straight paper channel delimited by wax. This analytical method was designed as a laboratory experiment for under graduates majoring in chemical education. The main objectives of this practice are to introduce [mu]PAD into a preservice teacher's classroom, motivating their passion of learning chemistry, and implementing green chemistry education. Finally, we hope this novel microscale chemistry experiment could be introduced into the chemistry classroom at high schools by these preservice teachers after graduation. A total of 145 preservice chemistry teachers performed this experiment in the fifth semester. They completed this experiment within 3 h; positive feedback from these students indicated that the learning objectives and instructional aims were met.

Science subjects at pre-tertiary and tertiary education levels are important for socio-economic and industrial development of any country; however, they are difficult for students to construct their concepts. In Tanzania, insufficient or lack of practical experiments are major challenges for science subjects due to insufficient or lack of laboratories, apparatus, expertise or reagents. Thus, this research assesses the effectiveness of paper-based against virtual laboratory experiences towards improvement of real (hands-on) chemistry practical in Tanzanian secondary schools focusing in Dodoma region. Chemistry virtual laboratory was developed and being deployed at Dodoma Secondary School for students who were never done practical sessions before to avoid biasness towards the study. The students were divided into three groups, namely paper-based and real laboratory as control groups (CG) and virtual laboratory as the experiment group (EG). Each group was further divided into two groups for the rest approaches forming six (6) groups. For EG, students were taught based on instructional approach which was enriched by computer animations in the computer laboratory. Results indicate that students who firstly attended virtual laboratory performed better in real laboratory than those who firstly attended real laboratory. Furthermore, the best progressive learning and performance for real experiments appears when the virtual laboratory preceded paper-based practical experiments. Thus, virtual laboratory is a very useful tool for learning chemistry practical not only to schools without laboratories but also to those with laboratories; and it should be considered by all the pre-tertiary schools in Tanzania and other schools in similar situations.

Gender inequality is strongly linked with poor performance in science and mathematics for female students in secondary schools owing to socio-economic and cultural issues as well as learning strategies. According to the Certificate of Secondary Education Examination results of 2021 in Tanzania, the failure rate for female students was higher than that for male students, and such failure in chemistry was associated with inadequate knowledge about the tested concepts, failure to identify the requirements of the respective questions and lack of adequate mathematical skills. Real practical sessions are integral parts of chemistry to enhance the learning environments for both female and male students. However, the real laboratory practices especially for chemistry are challenged with the costs of the construction of physical laboratory infrastructure and reagents, and the time-consuming and physical demands on personnel during real practical sessions. Thus, this study explores gender-based effects of the chemistry virtual laboratory against a paper-based approach towards a real chemistry practical in Tanzanian secondary schools. The results indicate that the combined exposures of virtual laboratory and paper-based practicals improve real practical performance for both female and male students. Moreover, the performance of real practical practices progressively improved for female students when they were first exposed to the virtual laboratory and then the paper-based practical. Such improvements can be associated with the virtual laboratory providing interactive learning environments which support female students to connect and engage.

The process of method development is at the heart of analytical chemistry, yet direct experimental experience with the process is rarely taught in the undergraduate laboratory. We report here an experiment that uses rapid, safe, and inexpensive paper-based microfluidics with cell phone detection in order to facilitate the development of a colorimetric method for the determination of iron with three different derivatizing agents (thiocyanate, 1,10 phenanthroline, or FerroZine). This lab has been developed with an inquiry-based pedagogy where students determine which figures of merit to measure, the order to measure them in, and their own procedures for measuring them. This experiment gives students the opportunity to measure linear range, sensitivity, selectivity, accuracy, precision, limit of detection, and optimal reaction time for each derivatizing agent. Students then compare and contrast the measured figures of merit to make an evaluation of which method is preferred for iron quantitation. The results are variable enough from group to group, and each derivatizing agent has different advantages and disadvantages so that there is no "right" answer. This experiment is very flexible and can be modified to fit into one or two lab periods, be delivered with students working in groups or individually, and be delivered in person or in a remote setting. Student learning was assessed using the Enhancing Learning by Improving Process Skills in STEM (ELIPSS) rubrics for management, critical thinking, and information processing. Students demonstrated growth in many skills and expressed significant appreciation for their own learning.

Chitosan, a renowned natural polymer for its wide application, was exploited for industry paper coating solutions. This research aimed to investigate the antimicrobial and water vapor barrier of chitosan solution-coated industry-manufactured paper. The papers were obtained from a national company in Indonesia. The commercially available chitosan with three molecular weight levels (low, medium, and high) was solubilized in sodium acetate buffer and subsequently utilized as the coating solution. The other variable studied was the chitosan concentration in the coating solution, i.e., 1.0, 1.5, and 2.0% (w/w). The antimicrobial activity study was performed by testing against Gram-positive bacteria, represented by Staphylococcus aureus, and Gram-negative bacteria, represented by Escherichia coli. The low molecular weight chitosan showed the best antimicrobial activity and water vapor barrier performance. The 1 %w low molecular weight chitosan-coated paper had shown good antimicrobial activity, against both S. aureus and E. coli, with a growth reduction of > 95 %. The most effective antimicrobial activity against S. aureus was achieved by paper coated with a 1.5% solution of low molecular weight chitosan. For low molecular weight chitosan-coated paper the most effective water vapor barrier was exhibited at 1 %w chitosan concentration. Having shown the best water vapor barrier while maintaining good antimicrobial activity, the 1.0% solution of low molecular weight chitosan was appointed as the best coating solution in this research.

The lack of time available for staying up to date with the literature is a common issue for scholars and practitioners in many disciplines. A recent challenge issued on Twitter with the goal to read 100 papers in 100 days attracted the attention of several members of the chemistry education research community. In this paper, we report the outcomes of this reading challenge, including insights into the group composition, its reading preferences, and challenges participants face. We also provide an overview of the themes covered in the group's readings obtained via natural language processing of the abstracts of the papers read by the group. Common themes in the papers were generally centered around students, learning, and chemistry, with an emphasis on research validity and the role of technology in chemistry instruction. Differences between individual participants' reading choices and those of the group as a whole are visualized using semantic network plots.

We introduced a microfluidic paper-based analytical device ([mu]PAD) to undergraduates majoring in nutrition education using a modified acid-base titration on paper microzones. After designing experiments for sample analysis using micro acid-base titration, students fabricated the devices and implement the experiment as designed. Then they designed and implemented a classical titration method to evaluate the analytical results obtained by micro acid-base titration. Finally, the students completed an instructional design for teaching at secondary or higher vocational colleges. This comprehensive experiment aims to expose students to [mu]PADs, ignite their passion in learning courses related to food analysis or chemistry, train their capabilities in designing an experiment, improve skills in instructional design, and facilitate education of [mu]PADs in secondary or higher vocational colleges. Fifty-three students majoring in nutrition education participated in this comprehensive experiment and completed instructional designs within 2 weeks (14 h) in the fifth semester. Positive feedback from students indicated that the learning objectives of this comprehensive experiment were met.

As an effective way for energy conversion, triboelectric nanogenerators (TENGs) have aroused great attention. Particularly, the paper-based TENGs have been paid the highest emphasize for their unparalleled merits: flexibility, light weight, low cost, and recyclability under heavily allocated environmental protection. To address drawbacks of paper-based TENG (e.c. susceptible to moisture, inflammability), here, an effective superhydrophobic-flame-resistant coating for superhydrophobic and flame-resistant dual-treated paper-based TENG is, firstly, proposed. This coating was obtained by in-situ addition of fire-retardants (polyhedral methyl-silsesquioxane and ammonium polyphosphate) during the process of sol–gel reaction of two silane precursors: tetraethyl orthosilicate (TEOS) and tridecafluorooctyl triethoxysilane (FAS). This superhydrophobic-flame-resistant coating endowed paper-based TENG with excellent surfacial hydrophobicity (water contact angle above 150°) and flame-resistant properties (limit oxygen index improved by 5% compared with original sample), simultaneously. Meanwhile, the coating also exhibits outstanding anti-permeability towards water (keep WCA last more than 1 h) and resistance towards acidic corrosion. The superhydrophobic-flame-resistant modification renders the obtained TENG to work with conventional properties under humidity environment and fire protection. This paper-based TENG feasibly powers LED and alarm apparatus, demonstrating its plausibility for new approach for advanced energy harvest and conversion.

The study demonstrates that cellulose filter paper modified with covalently chelating ligands (FP@Si@SaPh) is highly effective in removing Ni, Pb, and Cd ions from aqueous environments. Optimal adsorption efficiency for these metals was achieved at pH 6–7 at room temperature, with the adsorption order being Pb > Cd > Ni. FP@Si@SaPh can be regenerated using an EDTA solution and reused without significant loss in adsorption efficiency. Isotherm analyses revealed that the adsorption of Ni and Cd conforms to both Freundlich and Langmuir models, while Pb adsorption aligns best with the Langmuir isotherm. Investigating the adsorption mechanism by high resolution XPS analyzes showed that the adsorption was done both through coordination with Schiff base ligands and through non-bonding electron pairs of N and O atoms on the surface of filter paper. Tests on shrinkage and swellability confirmed that the filter paper maintains its quality through multiple wetting and drying cycles, allowing for repeated use, wherein 0.9 mg/L and 0.4 cm changes in swellability and shrinkage was observed after five consecutive cycles. Additionally, the filter paper demonstrates high selectivity for Ni and is suitable for selective heavy metal adsorption. Its antibacterial properties against Escherichia Coli bacteria suggest potential application in household water purification systems, where it can remove heavy metals and inhibit bacterial growth.

In this paper, we report a novel method for enhancing the flame retardancy of wood-based paper by utilizing natural biomaterials. The research constructed a bilayered structure coating on paper fiber surfaces, incorporating mixed starch (MS), adenosine triphosphate (ATP), and phytic acid (PA) as natural bio-based flame retardants. The structural configuration of the coating comprises MS/ATP and MS/PA, which were sequentially assembled as bottom and top parts, respectively, through pneumatic spraying. The surface morphological features and elemental distribution analysis of treated paper indicated that bio-materials were successfully assembled, which resulted in a uniform flame retardant coating on the paper fiber surface. Compared to the untreated paper, the limiting oxygen index of 20 bilayers (BL) treated paper increased substantially from 19.07% to 24.00%, and the thermogravimetric analysis showed out the residual char yield enhanced from 23.80% to 38.10% under nitrogen atmosphere. The cone calorimeter test results of 20 BL treated paper have approximately a 50.00% reduction than the untreated paper in both peak and total heat release rates. During thermal exposure, the top and bottom parts of the bilayered structure coating are successively flame retarded prior to paper fiber degrading. The method presented in this paper provides an environmentally sustainable approach for producing flame retardant wood-based paper.

This essay charts the way that ideas of nature, life and disease generated new approaches to Europe's documentary culture between roughly 1650 and 1950. Training its focus on the medium of paper, specifically the essay, reveals conceptual intersections between caretakers of libraries and archives and naturalists or physicians whose focus was the entomology or bacteriology. The recognition of the fundamentally organic nature of books (animal, vegetable, mineral, in a Linnaean sense) invited fresh vocabularies and practices of care and preservation. The essay first explores how book lovers—often encouraged by learned societies or state agencies in the eighteenth century—campaigned against insects whose habitat lay between the covers of precious tomes. It then traces how nineteenth-century microscopy and bacteriology informed notions of sickness or 'pathology' in books. It ends by describing the efforts to remediate these impairments in the twentieth century: to deploy chemistry and medicine as therapies for bringing imperilled papers back to health. [ABSTRACT FROM AUTHOR]

The chirality of chemicals is a well-known concept among undergraduates. The examples of chiral molecules in daily life are introduced to high school students as well. However, the chirality of single-walled carbon nanotubes (SWCNTs) remains unpopular in these groups. In this paper, a simple visualization of SWCNTs was first performed via paper origami. Then, a cost-effective separation experiment was introduced to the students to achieve the actual chiral SWCNTs. The proposed visualization and separation of chiral SWCNTs were evaluated in students' science projects. Introducing the chirality concept to students would enhance the students' understanding of nanomaterials and the chirality of SWCNTs.

We describe a paper-based microfluidic device for iron(III) assay in an applied instrumental analysis laboratory. Simple and convenient devices were fabricated by the students using patterning of filter paper to investigate three different procedures: drawing a boundary with eyeliner or wax pen; drawing a boundary with waterproof permanent marker pen; or drawing no boundary. These test papers were used for the analysis of iron(III) in water samples by smartphone-based colorimetric detection with thiocyanate. Additionally, the interference effect of other metal cations was done to further demonstrate practical utility. The results for field sample detection using this microdevice were satisfactory and show promise for use in other applications.

An inexpensive at-home quantitative analysis activity was developed for the determination of glucose in unknown samples using paper-based microfluidic devices. All of the materials and reagents for the activity fit in a small kit that was mailed to students. The only items students needed to supply were water and a smartphone. Microgram quantities of glucose were dried down in microcentrifuge tubes and included in the kit so that students could prepare external standards. Student results distinguished between two different concentrations of glucose that served as unknown samples. The combination of paper-based devices and dried-down microgram quantities of reagents provides a foundation for the development of other at-home or in-person experiments.

Due to the production of huge quantity of potentially toxic and recalcitrant pollutants, which cannot be completely decomposed with conventional biological wastewater treatment processes, in the paper industry, reliable treatment processes are highly required. This study conducted effective experiments of different series of processes to decompose persistent contaminants in the paper wastewater under controlled conditions of the used processes to meet the effluent quality standards of Korea Ministry of Environment in terms of CODMn (< 130 mg/L). For Biological treatment, Fenton, and photo-Fenton processes, various operational parameters were adjusted to determine the optimal conditions for CODMn value. Due to large quantity of refractory contaminants in the wastewater, single treatment process was not enough to meet the requirement of CODMn. Herein, we achieved the goal with two approaches: (1) secondary Fenton oxidation after biological and primary Fenton treatments, and (2) photo-Fenton treatment after biological treatment alone. The secondary Fenton oxidation process is an additional process operated under the same condition of the primary Fenton treatment to treat the effluent from the primary Fenton treatment. Ultimately, the residual CODMn concentrations of the secondary Fenton and single photo-Fenton treatment were 62.7 and 85.3 mg/L, respectively. However, the secondary Fenton required larger amounts of reagents and produced significant amounts of sludge, which require post-treatment, compared to single photo-Fenton treatment. Therefore, it suggests that the application of photo-Fenton was more efficient than the secondary Fenton in terms of economic feasibility and post-treatment requirement.

Pulp and paper manufacturing ranks as one of the most water and energy-intensive sectors globally, invariably leading to significant environmental pollution e.g. issues related to air pollution and waste disposal. Also, as global competition intensifies, prices of forest products are expected to keep decreasing. To ensure their viability, traditional producers must augment their revenue streams by diversifying into the production of bioenergy and biomaterials, alongside traditional wood, pulp, and paper products. A feasible solution is the integrated products biorefineries which provide a distinctive chance to pulp and paper industry to enhance revenues as well as reduce their environmental impact. Since pulp and paper stands as the predominant industry in Sweden, this review article explores the emerging biorefinery process options and main technological pathways being developed within Swedish pulp and paper mills. It also delves into the significant challenges that are being encountered in this evolving landscape and what possibilities lie ahead for responsible and sustainable pulp and paper operations.

As the Special Issues “Feature Papers in Photochemistry” and “Feature Papers in Photochemistry II” conclude, it is crucial to acknowledge the remarkable progress and persistent gaps that continue to shape the journey of photochemistry research [...]

This study presents an innovative lateral flow microfluidic paper-based analytical device (μPAD) designed for conducting quantitative paper-based enzyme-linked immunosorbent assays (p-ELISA), seamlessly executing conventional ELISA steps in a paper-based format. The p-ELISA device utilizes a passive fluidic circuit with functional elements such as a multi-bi-material cantilever (B-MaC) assembly, delay channels, and a buffer zone, all enclosed within housing for autonomous, sequential loading of critical reagents onto the detection zone. This novel approach not only demonstrates a rapid assay completion time of under 30 min, but also boasts reduced reagent requirements, minimal equipment needs, and broad applicability across clinical diagnostics and environmental surveillance. Through detailed descriptions of the design, materials, and fabrication methods for the multi-directional flow assay (MDFA), this manuscript highlights the device’s potential for complex biochemical analyses in a user-friendly and versatile format. Analytical performance evaluation, including a limit of detection (LOD) of 8.4 pM for Rabbit IgG, benchmarks the device’s efficacy compared to existing p-ELISA methodologies. This pioneering work lays the groundwork for future advancements in autonomous diagnostics, aiming to enhance global health outcomes through accessible and reliable testing solutions.

This article analyzes the prospects for the appearance of paper-based sensors on the sensor market. It is concluded that paper-based sensors are not a fantasy but a reality. It is shown that paper has properties that make it possible to develop a wide variety of paper-based sensors, such as SERS, colorimetric, fluorescent, conductometric, capacitive, fiber-optic, electrochemical, microfluidic, shape-deformation, microwave, and various physical sensors. The use of paper in the manufacturing of various sensors opens up new possibilities both in terms of new approaches to their manufacturing and in terms of new areas of their application. However, it must be recognized that for the widespread use of paper and the appearance of paper-based sensors on the sensor market, many obstacles must be overcome.

A recyclability perspective is essential in the sustainable development of energy storage devices, such as lithium-ion batteries (LIBs), but the development of LIBs prioritizes battery capacity and energy density over recyclability, and hence, the recycling methods are complex and the recycling rate is low compared to other technologies. To improve this situation, the underlying battery design must be changed and the material choices need to be made with a sustainable mindset. A suitable and effective approach is to utilize bio-materials, such as paper and electrode composites made from graphite and cellulose, and adopt already existing recycling methods connected to the paper industry. To address this, we have developed a concept for fabricating fully disposable and resource-efficient paper-based electrodes with a large-scale roll-to-roll coating operation in which the conductive material is a nanographite and microcrystalline cellulose mixture coated on a paper separator. The overall best result was achieved with coated roll 08 with a coat weight of 12.83(22) g/m2 and after calendering, the highest density of 1.117(97) g/cm3, as well as the highest electrical conductivity with a resistivity of 0.1293(17) mΩ·m. We also verified the use of this concept as an anode in LIB half-cell coin cells, showing a specific capacity of 147 mAh/g, i.e., 40% of graphite’s theoretical performance, and a good long-term stability of battery capacity over extended cycling. This concept highlights the potential of using paper as a separator and strengthens the outlook of a new design concept wherein paper can both act as a separator and a substrate for coating the anode material.

Superhydrophobic paper-based functional materials have emerged as a sustainable solution with a wide range of applications due to their unique water-repelling properties. Inspired by natural examples like the lotus leaf, these materials combine low surface energy with micro/nanostructures to create air pockets that maintain a high contact angle. This review provides an in-depth analysis of recent advancements in the development of superhydrophobic paper-based materials, focusing on methodologies for modification, underlying mechanisms, and performance in various applications. The paper-based materials, leveraging their porous structure and flexibility, are modified to achieve superhydrophobicity, which broadens their application in oil–water separation, anti-corrosion, and self-cleaning. The review describes the use of these superhydrophobic paper-based materials in diagnostics, environmental management, energy generation, food testing, and smart packaging. It also discusses various superhydrophobic modification techniques, including surface chemical modification, coating technology, physical composite technology, laser etching, and other innovative methods. The applications and development prospects of these materials are explored, emphasizing their potential in self-cleaning materials, oil–water separation, droplet manipulation, and paper-based sensors for wearable electronics and environmental monitoring.

In China, fruit tree diseases are a significant threat to the development of the fruit tree industry, and knowledge about fruit tree diseases is the most needed professional knowledge for fruit farmers and other practitioners in the fruit tree industry. Research papers are the primary sources of professional knowledge that represent the cutting-edge progress in fruit disease research. Traditional knowledge engineering methods for knowledge acquisition require extensive and cumbersome preparatory work, and they demand a high level of professional background and information technology skills from the handlers. This paper, from the perspective of fruit tree industry knowledge dissemination, aims at users such as fruit farmers, fruit tree experts, fruit tree knowledge communicators, and information gatherers. It proposes a fast, cost-effective, and low-technical-barrier method for extracting fruit tree disease knowledge from research paper abstracts—K-Extract, based on large language models (LLMs) and prompt engineering. Under zero-shot conditions, K-Extract utilizes conversational LLMs to automate the extraction of fruit tree disease knowledge. The K-Extract method has constructed a comprehensive classification system for fruit tree diseases and, through a series of optimized prompt questions, effectively overcomes the deficiencies of LLM models in providing factual accuracy. This paper tests multiple LLM models available in the Chinese market, and the results show that K-Extract can seamlessly integrate with any conversational LLM model, with the DeepSeek model and the Kimi model performing particularly well. The experimental results indicate that LLM models have a high accuracy rate in handling judgment tasks and simple knowledge Q&A tasks. The K-Extract method is simple, efficient, and accurate, and can serve as a convenient tool for knowledge extraction in the agricultural field.

The majority of chemical experiments conducted during educational programs are carried out in laboratories because they require instructors with special skills, in addition to large, expensive instruments. Recently, there has been an increasing demand for chemical experiments that can be carried out anywhere. Herein, we propose a novel type of paper-based analytical device (PAD) for enabling quantitative analysis without the requirement for a micropipette, since the PAD features a large sample loading zone and a waste zone, enabling accurate volume control of a liquid sample. We initially employed a micropipette to evaluate the PAD and demonstrate the quantitative analysis of ascorbic acid (AA) and pH using different loading volumes. Finally, we determined the AA concentrations and pH values of commercially available beverages using disposable plastic droppers, and the obtained results were in good agreement with those obtained through conventional methods. This PAD format can therefore be used as a novel educational tool for conducting certain chemical analyses in remote learning environments.

The primary objective of this research is to evaluate the feasibility of two of the most prevalent agricultural residues in Ecuador, banana peels and pineapple peels, as a carbon source in the culture medium of Komagataeibacter hansenii for the production of bacterial cellulose (BC) and BC-based paper. This analysis includes an assessment of the productivity parameters of the obtained BC and the quality parameters of the BC-based paper, employing multivariate statistical methodologies. The experimental design consisted of fifteen treatments: T1 served as the control using the standard HS medium, while treatments T2–T8 used banana peel extracts (BPE), and treatments T9–T15 used pineapple peel extracts (PPE) at concentrations from 10% to 40% (v/v). Extracts were prepared with tailored pretreatments for each type of peel to optimize bioactive compound recovery. Standardized fermentation and purification conditions were applied, and once the cellulose was obtained, additives and coating agents were incorporated to produce paper samples from each treatment. The results indicated that higher BPE concentrations (T5, T6, T7, and T8) correlated significantly with increased Weight and Yield of BC, as well as improved grammage and water content in the BC-based paper. This highlights that efficient paper production is influenced by the quality of the bacterial cellulose used, with BPE-based media yielding optimal results due to their nutrient composition, which promotes bacterial growth and metabolic activity. This approach suggests a pathway for advancing sustainable and economical paper production.

Fiber-reinforced polymer composites (FRPCs) present a promising solution for diverting waste generated by the pulp and paper industry from landfills. The global pulp and paper industry generated 110 million tons [...]

Paper and board are widely used as food contact materials. For such sensitive applications, consumer safety regarding the transfer of chemical components and contaminants to the food needs to be established. Such safety assessments are becoming increasingly challenging not only due to intentionally added substances but also non-intentionally added substances. In the European Union, compliance testing and safety evaluation of paper in food contact are largely based on national legislation and standards. The underlying tests are conventional methods, often overestimating and sometimes underestimating the migration into food. In this article, the relevant standard test methods are contrasted with currently available scientific knowledge. The scientific approaches to develop and identify suitable test methods are critically reviewed. Furthermore, theoretical predictions via mathematical modeling, with the aim to realistically simulate transfer to food, are presented and discussed in comparison with available migration studies with foods. Objectives are to (i) summarize the actual scientific knowledge in the field and draw conclusions regarding the potential and limitations of the existing test methods and (ii) identify research gaps toward a better qualitative and quantitative understanding of transport processes of volatile and non-volatile substances from paper and board into foods.

The Making Introductory Courses Real while Online (MICRO) laboratory project was developed to meet the need for hands-on experiments, focused on topics in analytical chemistry, to be delivered safely remotely or in a socially distanced in-person lab. Unlike more traditional lab experiments, MICRO laboratories use only microgram or nanogram amounts of chemicals; paper microfluidic technology is used to store and mix reactants. Instructional materials use an inquiry-based approach and are situated in a context that highlights the human impacts of the scientific analysis. To support broader-scale implementation of the experiments and promote a shift to more inquiry-based laboratory instruction, an array of supports were developed, including adaptable instructional materials, instructional videos for lab preparation, resource guides, and an introductory workshop. A cohort of nine institutions implemented MICRO laboratories both remotely and in person during Fall 2020. Students were able to successfully complete the experiments, and the inquiry nature of the laboratories led to an increased comfort with the trial-and-error nature of authentic scientific practice. Additionally, most faculty participants indicated a commitment to an increased degree of inquiry in their laboratory pedagogy.

The fraudulent practice of adding ammonium salts to milk in order to enhance the nitrogen content has serious health implications including renal failure. Ammonium ion detection has been targeted through the conventional analytical methods however, lack of portability and complex operation limits their use for field applications. In this scenario, paper-based test strips and electrochemical sensors can provide strategies for point-of-test applications. Here, an ion-selective paper-based chromogenic strip and an electrochemical sensor has been developed for detection and quantification of ammonium ions. The developed paper-based chromogenic strip showed detection limit of 0.008 % (w/v) for ammonium ions, whereas, electrochemical sensor showed an LOD of 0.0062 ± 0.0023 % (w/v) with a sensitivity of 1.6 × 10−5 A.% −1.mm−2. The developed paper-based chromogenic strip and electrochemical sensor can be employed by regulatory bodies and dairy industries to ensure the safety and quality of milk.

The current study describes the in-situ growth of ZnS/MoS2 on cellulose paper using the thin-film microextraction (TFME) method. On cellulose paper, ZnS/MoS2 was grown using a simple, easy, and inexpensive hydrothermal method. The digoxin was quantified after TFME using high-performance liquid chromatography-UV detection (HPLC-UV). The effect of effective parameters such as extraction time, extraction temperature, agitation speed, and sample ionic strength was investigated, and the best conditions were selected. Under ideal conditions, a calibration curve with good linearity (R2=0.987) and a low limit of detection (LOD) in the range of 0.01–100 ng mL-1 was obtained. The detection limits were 0.03 ng mL-1. For the digoxin, the relative standard deviations (RSDs) were 5.3%. The method was successfully applied to the study of urine and plasma. Relative recoveries were found to range between 96% and102 %. The proposed method provided a straightforward, efficient, and environmentally friendly way for determining digoxin in real-world samples.

The use of synthetic chemicals in acid‒base testing has raised concerns about their environmental impact. The use of natural materials to produce natural indicator paper is an attempt to reduce the negative impact on the environment. Binahong (Anredera cordifolia) seeds can replace conventional chemical synthetic materials. This study aims to develop Binahong seed indicator paper as an alternative environmentally friendly material for acid‒base testing. The method used in this research is experimental and involves the extraction of Binahong seeds, making indicator paper with a certain formulation, and testing the performance of the indicator paper using standard acid and base solutions. Data collection was performed via the observation and measurement of certain parameters. The test results of the Binahong natural indicator paper revealed a significant color change when 95% ethanol was used, which produces a red or purple color at pH 1‒7, a blue color at pH 8‒10 and a yellow color at pH 11‒14. Binahong seeds have potential as an environmentally friendly alternative in acid‒base testing because they respond well to variations in the acidity and basicity of the solution.

A unique triboelectric nanogenerator (TENG) using carbon nanotube (CNT) composite papers is proposed in this work. CNT composite papers can be fabricated easily using a method based on the production of Japanese washi paper. To obtain and evaluate the proposed TENGs, several types of CNT composite papers and aluminum plates were prepared. As the CNT composite paper contained many paper fibers, it was expected to be negatively charged, and the aluminum plate was expected to be positively charged across the triboelectric series. Through various experiments, it was confirmed that CNT composite papers could be used as TENGs. In addition, it was found that when a CNT composite paper was used, it contributed to triboelectricity generation, and the contained CNTs efficiently transferred the generated charge to the electrodes. Furthermore, output voltages approaching a maximum RMS value of 300 mV could be obtained. The results of this study will aid in the practical application of paper-based TENGs in the near future.

Microfluidic paper-based analytical devices (µPADs) have been successfully developed using dual detection: electrochemical and colorimetric systems. The µPADs have the potential to be used as Pb(II), Cd(II), and Cu(II) sensors to test the quality of water. The fabrication process uses hot embossing and screen-printing methods. The working electrode in the electrochemical zone was enhanced by the bismuth metal deposition process, while in the colorimetric zone, the gold nanoparticles modified with thioctic acid and dansylhydrazine (TA-Au-DNS) were used as a colorimetric sensor to detect Cu. The basic material of µPADs was characterized using a Fourier-transform infrared (FTIR) and a contact angle meter (CAM). In the electrochemical zone, the signals of square wave anodic stripping voltammetry (SWASV) resulted in good detection of Pb(II) and Cd(II) (from 0 to 100 ppb) with a limit of detection of 1.588 and 1.42 ppb, respectively. In the colorimetric zone, the performance of TA-Au-DNS for detecting Cu metal was obtained from readings through the red-green-blue (RGB) sensor as a miniature of µPADs reader. The LOD, LOQ, and average Vx0 (linearity values) in the detection of Cu(II) (from 58 to 100 ppb) are 8.51 ppb, 28.36 ppb, and 0.41%, respectively.

This work reports the first use of rubber latex waste as the hydrophobic reagent for a low-cost, simple, and rapid fabrication of a paper towel-based experimental device (PTED) with a circular design of 5 mm to demonstrate the factors affecting chemical equilibrium; this serves as a user-friendly means for a laboratory experiment. The illustration of the factors affecting chemical equilibrium is implemented in the PTED. In this approach, the color change of a cobalt(II) complex reaction from pink to blue was observed by the naked eye on the PTED when a tiny drop of hydrochloric acid solution and the treatment of heat by using a hot air dryer (1200 W, 2 min) were applied to the PTED with the precoated cobalt solution (pink color), separately or together. The return of the color of the reactions from blue to pink was carried out by using a tiny drop of water and the treatment of cooling by using an ice bath for 10 min. In addition, the chemical equilibrium constant ("K"[subscript c]) can be easily quantified by processing digital images of the detection zones of PTED captured with a smartphone camera under a control light box at room temperature (˜25 °C), while image analysis was performed using ImageJ software. This PTED laboratory is a new approach not only to enhance students' learning of the factors affecting chemical equilibrium based on Le Châtelier's principle, but also to present potential applications of PTED into all levels of chemistry from middle school through college classes.

A two to three period analytical chemistry experiment has been developed which allows second year students to explore chemical color tests used to detect adulterated pharmaceuticals. Students prepare several paper analytical devices (PADs) to generate positive and negative controls antibiotics, along with cutting agents such as starch and chalk. These PADs are used to identify the active ingredients and excipients in mystery tablets prepared by their classmates. In the second part of the lab, the students select an individual color test and design an experiment to quantify their mystery pill's active pharmaceutical ingredient (API). Nearly all of the student groups were able to successfully identify adulterants present in their mystery tablets. The quantification of the mystery tablets was also successful with all but one group calculating the correct concentration within 6%. In a postlab assessment, the students identified their largest gains in their ability to analyze data and other information, skill in science writing, and learning of laboratory techniques.

With the advent of artificial intelligence digitization, intangible cultural heritage faces challenges in preservation and transmission. Utilizing modern technology to achieve digital protection and dissemination has become a crucial issue today. This study enhances the digital inheritance and development of Chinese intangible cultural heritage paper-cutting art through generative AI technologies, specifically Diffusion and LoRA models. The Analytic Hierarchy Process (AHP) was employed to categorize the cultural value of paper-cutting, selecting four core elements: “Spring Festival”, “Chinese Zodiac”, “Women”, and “Birds and Flowers”. Based on these, eight LoRA models were developed to generate paper-cutting-style patterns (using the FLUX.1-dev and Stable Diffusion 1.5 models). In the user satisfaction assessment, the Importance–Performance Analysis (IPA) method was used to analyze four dimensions of the model experience. The results indicate that the LoRA model excels in generating detailed paper-cutting patterns and accurately reproducing cultural elements, particularly in the generation of complex Chinese character designs. User feedback suggests that the LoRA model effectively enhances the digital representation and dissemination of paper-cutting art, though there is room for improvement in terms of generation speed and ease of operation. This study provides a new technological pathway for the digital preservation of intangible cultural heritage and promotes the modernization of paper-cutting art transmission.

When the power converter connects to the high-frequency transformer breaks through the bottleneck and reaches a frequency of 100 kHz or even higher, the high-frequency transformer’s inter-turn insulation faces more serious high-frequency discharge and high-temperature problems. In order to improve the service performance of oil-immersed high-frequency transformer insulation paper, composite K-BNNS particles are prepared by ultrasonic stripping, heat treatment, and thermomagnetic stirring. Then, K-BNNS particles are mixed with PMIA (polymeric m-phenylenediamine solution) slurry to produce composite aramid paper. And the effects of K-BNNS particles with different contents on the thermal conductivity, dielectric properties, partial discharge properties, and mechanical properties of aramid paper are explored. It can be found that, when the addition of composite particles (K-BNNS) is 10%, the comprehensive performance of composite aramid paper is the best. Compared with Nomex paper, the in-plane and through-plane thermal conductivity of composite insulating paper F-10 increased by 668.33% and 760.66%, respectively. Moreover, the high-frequency breakdown voltage increased by 48.73% and the tensile strength increased by 2.49%. The main reason is that the composite particles form a complete thermal conductive network in the aramid paper matrix and a large number of hydrogen bonds with the matrix, which enhances the internal interface bonding force of the material and changes the charge transport mechanism.